Problem: Simplify the expression. $(-n-7)(-n-5)$
First distribute the ${-n-7}$ onto the ${-n}$ and ${-5}$ $ = {-n}({-n-7}) + {-5}({-n-7})$ Then distribute the ${-n}.$ $ = ({-n} \times {-n}) + ({-n} \times {-7}) + {-5}({-n-7})$ $ = n^{2} + 7n + {-5}({-n-7})$ Then distribute the ${-5}$ $ = n^{2} + 7n + ({-5} \times {-n}) + ({-5} \times {-7})$ $ = n^{2} + 7n + 5n + 35$ Finally, combine the $x$ terms. $ = n^{2} + 12n + 35$